Electronic trip units currently used within industrial circuit breakers rated in excess of 150 amperes and having AC voltages in excess of 600 volts require current sensing transformers in a size proportional to the circuit breaker ampere current rating. U.S. Pat. No. 4,482,877 to Roger Castonguay et al. and the background patents referenced therein describe a molded case industrial rated circuit breaker having an ampere rating in the range of 10-150 amperes and from 120-600 volts AC. Heretofore, it has been economically unfeasible to use an electronic trip unit with smaller sized ampere rated breakers, since size constraints and cost requirements for the current transformers and the electronic circuitry were prohibitive. Recently issued U.S. Pat. No. 4,589,052 to John Dougherty describes a miniaturized electronic trip unit wherein the electronic components are implemented on a printed wiring board and is described as a "Trip Chip". The Dougherty printed wire board readily fits within the lower ampere rated circuit breakers as a replacement for the thermal magnetic units currently employed. U.S. patent application Ser. No. 679,660, filed Dec. 7, 1984 now U.S. Pat. No. 4,591,942, entitled "Current Sensing Transformer Assembly" in the names of H.G. Willard at al., describes a relatively inexpensive current sensing transformer that is economically feasible for use within lower ampere rated breakers. When current sensing transformers are used within the aforementioned higher ampere rated molded case circuit breakers, some additional means of electrical connection is required to connect the current sensing transformers with the electronic trip unit circuit. Male plugs and female receptors or the like are often employed for connection which is difficult to achieve on automated assembly equipment.
The instant invention relates to an economic arrangement for mechanically and electrically interconnecting three such current sensing transformers with a trip chip printed wiring board in a fully automated assembly process without requiring any additional connection means whatsoever.